Suspension dilemma: KW or JRZ?

[bigjae1976]

Originally Posted by Porschefile

I have KW CS and like them a lot, but I've always wondered what makes the JRZ better. I understand it is better built, but does that translate into an actual lap time improvement or is it just like "my rolex is better built than your watch" but it does the same thing.

Are JRZ/Moton/whatever actually faster than the track oriented KW's, and if so, is it a difference that a normal track driver can appreciate, as opposed to a .2 second benefit that only a handful of even experienced drivers can appreciate?

I don't think you'll ever find that information unless some magazine does a comparison test.

I like JamesClay's discussion. He should stop f'ing with his projects and talk to us. We're more fun. But his people that answer the phone are pretty knowledgable about a handful of products, pretty straight forward people. I talked to them for awhile about my E46. They did throw the JRZ thing in my face but we mostly talked about the TC Kline S/D vrs AST 4200s vrs Ground Control. In the case of my E46, I didn't even consider the KWs because they have strut tube to wheel clearance issues on the non-Ms. Won't allow the fitment of 255s on the front. KWs should be in the discussion for an E9X M3 though.

I think Bimmerworld has Turner beat in the coilover department because Turner's selection seems somewhat limited (that is my opinion). But I'm sure Turner can provide some expert insight as well. I believe Turner is starting to get some factory support for their racing program? If true, that may give Turner some extra insight into the chassis and suspension design. Bottom line...talk to some good vendors (Bimmerworld, Turner) who use the product in your projected applications (street, track, auto-x) and then try to ride in the car with a similar setup.

[Porschefile]

I agree that I doubt any person or company will share that information. But I think that fact speaks for itself. If JRZ's were 2 seconds faster than KW CS with the same track same driver then JRZ would love to tell everyone that fact.

I don't doubt that they are better made pieces, I just doubt that that will translate into a substantive improvement in performance.

[bigjae1976]

Originally Posted by Porschefile

I agree that I doubt any person or company will share that information. But I think that fact speaks for itself. If JRZ's were 2 seconds faster than KW CS with the same track same driver then JRZ would love to tell everyone that fact.

I don't doubt that they are better made pieces, I just doubt that that will translate into a substantive improvement in performance.

True. There are so many variables which render lap times as not a true comparison.

I look at the long-term costs. Not only how long they will last but what if I need to upgrade to springs? Can these coilovers "grow" with me as my skill (hopefully) increases? What if I decide to change the focus of the car? What if I decide to daily drive the car more? What about running R-Comps, slicks, street tires, etc.

Also, you have to look at the support that comes along with the coilovers. If you ask me, that's also a cost issue. If you have better support and data on the coilver/car setup from the vendor/manufacturer...then you'll get things right faster and you're not spending money in the form of frustrating track days trying to dial things in. From my recent shopping experience, the support your get is the biggest variable. I went with TC Kline because they can pretty much tell you how to setup a stock E46 right out of the box based on their testing.

[Beedub]

as a kw clubsport user myself.... i have to chime in here, i actively choose the clubsports due to their fantastic quality, their valving isnt to be sniffed @ either and is pretty awesome!!

but i agree with above my clubsports will allow me to "gro" as a driver, after a good few years with my car on stock suspension i KNEW what i wanted and the kw clubsport offers me that @ a semi reasonable price.
The car feels very impressive, very impressive indeed, the fit on these things was nothing short of perfection, again this is very important to me, for me the kw clubsport offered everything i need and more.

Cant wait to get some cup tyres on and go hunting!!!

JRZ, MOTON, Ohlins..... all equally awesome in their own right.....

[STALKER]

Im probably the only person on the forum that has used KW CS and JRZ RS1, both with 500/800 spring rates. I have used both on my daily drive, which is about 50-60km, which includes downtown roads and freeway. I have tracked both set ups.

I can say with out a doubt, the JRZs do everything better and are well worth the extra cost, especially for your daily commute, the ride quality is far superior. The KWs were very good out on track actually, I had no issues with them for track use.

One extra note, having great vendor support is also very important. James@Bimmerworld has always responded to my questions quickly and really helped me dial in my set up to where I am extremely happy with it. My local shop that does the work on my car is also very competent which is another must IMO.

[kaiv]

Thanks for the input, everyone.

Over the past couple of days I've ridden in a Z4M and driven an E90 M3 both equipped with KW clubsports. In the street of LA and SD respectively. Both were adjusted somewhere in the middle of the adjustment range and both felt firm but fine on the streets. Actually the E90 similar to my previous E90 equipped on V3s.

So I'm even more confused now *sigh*

[flipm3]

Originally Posted by kaiv

Thanks for the input, everyone.

Over the past couple of days I've ridden in a Z4M and driven an E90 M3 both equipped with KW clubsports. In the street of LA and SD respectively. Both were adjusted somewhere in the middle of the adjustment range and both felt firm but fine on the streets. Actually the E90 similar to my previous E90 equipped on V3s.

So I'm even more confused now *sigh*

I think you have to hop in a car with JRZ RS1s

[kaiv]

Originally Posted by flipm3

I think you have to hop in a car with JRZ RS1s

I would love to but not a soul in Socal has them. Actually on this entire forum it appears only STALKER has a set and he's in Canada

[slicer]

I have the KW Clubsport 3-ways and love them. I used to have Eibach springs on the EDC dampers. I have not felt a significant compromise on the street and in fact like the ride of the KW's better. I have not yet had them on the track so I can't speak to their performance in that environment. Send me a PM if you would like to sample the clubsports.

[bigjae1976]

If you've rode in a car with KW CSs and they meet your needs...why not? But if I had to make this decision...I'd go with the JRZs. Nothing worse than buyer's remorse later on and then having to spend more money to getting what you really want.

[klammer]

Originally Posted by bigjae1976

If you've rode in a car with KW CSs and they meet your needs...why not? But if I had to make this decision...I'd go with the JRZs. Nothing worse than buyer's remorse later on and then having to spend more money to getting what you really want.

+1
Buyers remorse :

[kaiv]

That's one way to put it. The other side of buyer's remorse is when you realize you spent ~$4k on a set of RS1 and $2.8k KW CS are just as fast

There's a sizeable price gap here. I was happy with the $2k V3s with GC street plates but I'm willing to try something new/different. I'm also OK with spending more but I don't want to ever wonder where my money went. So basically if I do spend that much more I want a setup that's going to be noticeably faster and better out of the box.

I appreciate everybody's input but so far it seems that everybody who favors JRZ doesn't actually have any experience with the RS1 (yes yes the RS and RS Pro are awesome, apples to oranges).

STALKER, who does have experience said they are much faster but he also switched from NT05s to R-S3s at the same time he switched suspensions. So that throws everything off, tires are a HUGE variable. Having personally tracked both tires; the NT05 is decent but feels like an all season when compared to the R-S3

I apologize if I'm ranting. It's just frustrating to have to rely on hearsay when you're contemplating spending that much money. I wish we could just try suspension setups like helmets or seats.

Thanks everyone.

[kaiv]

PS: FWIW, I run advanced/open passing and instruct beginners.

[bigjae1976]

I think James Clay gave you a good objective comparison and you have lots of useful opinions. But I think you're looking for data that no one has...a direct comparison of lap times between the 2 coilovers? I've never seen that anywhere for any model.

Not sure what else we can provide on the forum. Recommend you do some old fashioned dialing. You'll probably get somewhere a lot faster.

On the buyer's remorse thing, I'd rather overspend once than underspend and then spend again. I've been down that road a couple of times and learned my lesson. I think moreso with BMWs and even more often with Ms that parts are marketed as upgrades but they actually turn out to be inferior. You really do need to spend money on parts to get something truly better.

[STALKER]

Originally Posted by kaiv

That's one way to put it. The other side of buyer's remorse is when you realize you spent ~$4k on a set of RS1 and $2.8k KW CS are just as fast

There's a sizeable price gap here. I was happy with the $2k V3s with GC street plates but I'm willing to try something new/different. I'm also OK with spending more but I don't want to ever wonder where my money went. So basically if I do spend that much more I want a setup that's going to be noticeably faster and better out of the box.

I appreciate everybody's input but so far it seems that everybody who favors JRZ doesn't actually have any experience with the RS1 (yes yes the RS and RS Pro are awesome, apples to oranges).

STALKER, who does have experience said they are much faster but he also switched from NT05s to R-S3s at the same time he switched suspensions. So that throws everything off, tires are a HUGE variable. Having personally tracked both tires; the NT05 is decent but feels like an all season when compared to the R-S3

I apologize if I'm ranting. It's just frustrating to have to rely on hearsay when you're contemplating spending that much money. I wish we could just try suspension setups like helmets or seats.

Thanks everyone.

I do agree the RS3s have more grip, but would not say the NT05 is like a all season tire compared to them.
To make it even harder, Ohlins R&T should be out soon as well.

[Porschefile]

I think there is a reason nobody has ever posted a lap time comparison between good track-oriented coilovers and their more expensive competitors.

The buyers remorse argument is a little silly. You have to draw the line somewhere right? Or else we'd all have Ohlins TTX or similar $15k setup?

I'm very pleased with my KW CS, and would be shocked if JRZ's are more than a couple of tenths faster if at all. From what I understand, the biggest actual difference between the really high end stuff and the assembly line stuff is the difference adjustments make. I do think that JRZ or whatever would respond more to rebound/comp adjustments, which is worth something. Whether that's worth the price increase is a personal choice; it isn't worth it for me.

[rzm3]

Originally Posted by kaiv

PS: FWIW, I run advanced/open passing and instruct beginners.

In this case, I think you will definitely appreciate being able to independently adjust compression and rebound. It's really not that hard assuming you can drive more or less consistently and feel the car. I can send you an adjustment flow chart from Allan Staniforth's "Competition Car Suspension".

Originally Posted by Porschefile

I think there is a reason nobody has ever posted a lap time comparison between good track-oriented coilovers and their more expensive competitors.

As an mechanical engineer I try to quantify and test the performance improvement of every modification I buy. However, the challenge is that it takes a lot of money and time to do it.

You need access to a race track under similar if not the same conditions, the tools/equipment to swap parts, a pro/advanced driver who can run consistent lap times, and data logging devices. I did it with my KW Competition here, but it took a ton of time and money.

Plus, many people who modify their cars 'for performance' never drive consistently enough to appreciate the real difference anyway. Some never even see the race track. All you get these days is seat of the pants feedback.

Originally Posted by Porschefile

I'm very pleased with my KW CS, and would be shocked if JRZ's are more than a couple of tenths faster if at all. From what I understand, the biggest actual difference between the really high end stuff and the assembly line stuff is the difference adjustments make. I do think that JRZ or whatever would respond more to rebound/comp adjustments, which is worth something. Whether that's worth the price increase is a personal choice; it isn't worth it for me.

In terms of the JRZ, if it is anything similar to the typical JRZ/Moton racing dampers, I think it may perform better on very bumpy tracks/roads because you can adjust high-speed compression, which KW's 2-way can't do. Nonetheless, KW Clubsport's high-speed damping is tuned based largely on testing/simulation at the Nürburgring, which is a bumpy track to begin with.

[Beedub]

interestly my z4m set were over 2k in GBP so like 3400 bucks..... i know pricing is different all over the world but for me these were by no means the cheaper choice. i researched them, rode in a car with them, spoke to kw over and over again...... in the end i made my order.

[klammer]

Great thread with some good insights. Guess I'm in a slightly different boat as I plan (plans change) on paying up for a more comfortable street option coilover and that's where I think the JRZ shines in my case. Would agree with others that a dramatic difference in lap times probably doesn't exist (although it might) but comfort on the street does. I'm trying to build a true dual performer that can go on road trips and out to dinner and hang with vettes, vipers, gt-r's and gt-3's (not too worried about much else) I believe it's this true dual purpose that costs a premium and that's where I'm looking for value in the set-up... But that's just me...

[kaiv]

Originally Posted by STALKER

I do agree the RS3s have more grip, but would not say the NT05 is like a all season tire compared to them.
To make it even harder, Ohlins R&T should be out soon as well.

You are correct, I exaggerated a little bit there

Agreed, the Ohlins R&T are coming out and I was told MCS is coming out with a high end one way damper too.

Originally Posted by rldzhao

In this case, I think you will definitely appreciate being able to independently adjust compression and rebound. It's really not that hard assuming you can drive more or less consistently and feel the car. I can send you an adjustment flow chart from Allan Staniforth's "Competition Car Suspension".

I lap within the same second assuming I'm not hooning and there is no traffic but I am however completely clueless when it comes to adjusting the suspension.

For example: I had my V3s set at KWs recommended starting point settings. It felt fine to me, on both the street and the track so I never adjusted them.

Could I benefit from adjusting them one way or another? Most likely. I just have no clue.

I absolutely cannot tell if I need more or less rebound or more or less compression nor if I could benefit from either adjustment...

I understand what each does, on paper. But I cannot "feel".

And from talking to fellow track buddies it seems a lot of us are in that boat.

This is actually turning out to be the main thing that draws me to the RS1. High end damper but with a single knob for simplicity's sake.

Originally Posted by Beedub

interestly my z4m set were over 2k in GBP so like 3400 bucks..... i know pricing is different all over the world but for me these were by no means the cheaper choice. i researched them, rode in a car with them, spoke to kw over and over again...... in the end i made my order.

I'm from Europe so I know what you mean!
And an E92 M3 in the UK MSRPs at around 55k GBP which is over $85k converted in USD (US MSRP is $62k) //off topic

Originally Posted by klammer

Great thread with some good insights. Guess I'm in a slightly different boat as I plan (plans change) on paying up for a more comfortable street option coilover and that's where I think the JRZ shines in my case. Would agree with others that a dramatic difference in lap times probably doesn't exist (although it might) but comfort on the street does. I'm trying to build a true dual performer that can go on road trips and out to dinner and hang with vettes, vipers, gt-r's and gt-3's (not too worried about much else) I believe it's this true dual purpose that costs a premium and that's where I'm looking for value in the set-up... But that's just me...

KW V3s fit your exact needs if you ask me!

[bigjae1976]

Originally Posted by Porschefile

The buyers remorse argument is a little silly. You have to draw the line somewhere right? Or else we'd all have Ohlins TTX or similar $15k setup?

I think it certainly applies and especially for car mods since budgets are generally limited. So it all comes down to a trade off somewhere down the line. Either you spend less or wait longer to buy something over time. I can think of many examples where if I would have spent a little more and been a little more patient, I would have been happier and spent less money in the long run.

Honestly, your statement makes no sense. Of course there is a limit. As an example, you're saying if I was comparing an 330Ci vrs Lexus is300 vrs Infiniti G35 vrs Audi A4...all within my price range...then I look at an e46 M3 which I can also afford. You're saying that I can also consider an M5...because if I get the M3 I might regret not getting the M5 I cannot afford. If the OP cannot afford the JRZs then its an easy decision but he asked for information on the comparison because he likely can afford either system.

For example, I wanted to buy a 4 wheel BBK for my 330. I had saved up for a 4 wheel stoptech but ended up spending $1500 less on a UUC/Wilwood BBK. Let's say I spent much more in pads and rotors and really didn't get a big benefit in braking power or heat capacity. I ended up going with the Stoptechs 3 years later and now I am very happy. I sold the kit and lost $1800 in depreciation plus the 3 sets of rotors and 6 sets of pads I chewed through.

I estimate that if I had the Stoptechs from the get go, I would have went through fewer pads and rotors and never paid that $1800 in depreciation. Maybe I would have had to rebuild the calipers...about $300 for all 4 corners.

That's my example of buyer's remorse. I think that certainly applies here in a coilover decision. Its never just swapping out some parts. Alignments, setup, some parts (i.e. spring perches) need to be redone. Plus whatever time you spent tweaking your system because you're trying to get the best setup is wasted. All of that time on the track costs. That's the approach I took when looking at coilovers.

[Porschefile]

Fair enough. But it always comes down to the particular buyer and goals, and eventually you have to draw the line in the sand and say, well yeah I'd love Ohlins, but these dampers should be sufficient. I doubt many of us would experience buyer's remorse with KW CS like you did with UUC's "bbk".

Sorry, guess I get a little defensive over my coilovers

But that should be a good sign for people on the fence about them. I plan on making my car a full blown GTS4/5 racecar eventually, and I think the KW CS are sufficient for that (my opinion obviously).